Circuit breaker



Jan. 2, 1934. 0. K. MARTI 1,941,567

CIRCUIT BREAKER Filed June 27, 1931 2 Sheets-Sheet 1 /n yen/0r I Uf/Jmar A. Narh Jan. 2, 1934. 0 K. MART! 1,941,567

C IRCUIT BREAKER Filed June 27, 1931 2 Sheets-Sheet 2 /n yen/0r O/hmar K. Mar/7 Patented Jan. 2, 1934 1,941,561 CIRCUITBREAKER Othmar K. Marti, Haddonfleld, N. J., assignor,

by mesne assignments,

to Allis-Chalmers Manufacturing Company, Milwaukee, Wis, a corporation of Delaware Application June 27, 1931. Serial No. 541,222

11 Claim.

This invention relates to improvements in electric circuit breakers and particularly to circuit breakers in which the electric current is interrupted by interruption of an arc flowing through 6 a condensable conductive vapor. It has already been proposed to use a structure similar to an electric current rectifier of the metallic vapor type for the purpose of interrupting an electric circuit. It has been found lo'however that the voltage drop through a strucelectric current in which an arc, struck between a vaporizable electrode and a solid electrode upon separation of the electrodes, is quenched by rapid condensation of the vapor carrying the are which vapor rises from the vaporizable electrode.

Another object of the invention is to provide a circuit breaker for electric circuits in which an arc, struck between a vaporizable electrode and a solid electrode upon separation of the electrodes, is quenched by causing the are carried by the vapon from the one electrode to flow through a restricted passageway in which the vapor is intensely cooled thereby quenching the arc.

Another object of the invention is to provide a circuit breaker for electric circuits in which an arc, struck between a vaporizable electrode and a solid electrode upon separation of the electrodes, is quenched by causing the are carried by the vapor from the vaporizable electrode to flow through a restricted passageway which is provided with mechanical means for interrupting the arc.

Another object of the invention is to provide a circuit breaker for electric currents in which an arc, struck between a vaporizable electrode and a movable solid electrode upon separation of the electrodes, is transferred to a fixed solid electrode and is quenched by cooling surfaces arranged to force the arc to flow in a circuitous path.

Another object of the invention is to provide a circuit breaker for electric circuits in which an arc, struck between a vaporizable electrode and a movable solid electrode upon separation of the electrodes, is transferred to a fixed solid electrode and is quenched by electrical means repelling the vapor carrying the arc.

Another object of the invention is to provide a circuit breaker for electric circuits in which an are, struck between a vaporizable electrode and a solid electrode'upon separation of the electrodes, is quenched by a combination of mechanical means interrupting the arc and electrical means repelling the vapor carrying the arc.

Objects and advantages, other than those above set forth, will be apparent from the following description when read in connection with the accompanying drawings in which:

Figure 1 is a vertical cross sectional view through an embodiment of the invention shown somewhat diagrammatically,

Fig. 2 is a fragmentary view of a structure similar to that shown in Fig. 1 but illustrating mechanical means for interrupting the arc,

Fig. 3 is a view similar to that shown in Fig. 1 but illustrating the use of a solid electrode both for striking an arc and to which the arc is transferred, and

Fig. 4 is a modified form of the structure shown in Figs, 2 and 3, in which modification a movable solid electrode enters the side of the container of which the top serves as the fixed solid electrode and in which both electrical and mechanical means are employed to aid in interrupting the circuits.

Referring more particularly to the drawings by characters of reference, and considering first the embodiment of the invention as illustrated in Fig. 1, the circuit closing and circuit opening action takes'place within a tank which is, preferably, highly evacuated and whch comprises a bottom section, an intermediate section and a top section. Of the respective sections, the bottom section 6 may be formed as a frustrum of an inverted hollow cone which is closed at the bottom by a plate 13, spaced from the bottom by an insulating ring 14, to form a well for the purpose of receiving and retaining an electrode 16 of vaporizable material, such as mercury, which is conductive in the vaporous state. The intermediate section 7 of the tank is formed as an annular cooling chamber through which a cooling medium, such as water or other fluid of relatively high heat conductivity, may be circulated by way of the inlet 21 and the outlet 22, provided for such purpose in the outer vertical wall. The section 7 is additionally provided with an aperture 9 formed by the inner vertical wall 10, which may preferably be of wardly projecting fins 23, formed of any suitable heat and mercury resisting material, aflixed to the wall 10. The top section 8 is formed as a vapor receiving and condensing chamber having an upwardly extending section 26, and constitutes a housing for and supports the movable operating elements of the device.

The walls of the respective sections 6, 7 and 8, comprising the casing, may be formed of any suitable heat and mercury resisting material and, as shown, are joined together in a gas tight manner by the rings 11 and 12 formed of suitable insulating material. The circuit to be controlled, as indicated by the conductors 17 and 38, are connected with the device through the cathode plate 13 and the walls of the section 8 of the casing respectively.

As one means for efiecting movement of electrode 27 into circuit closing connection with the electrode 16, I provide a solenoid magnet 34 and an armature 33 therefor supported within the extension26. The armature 33 is shown as connected with the lazy tong lever members 28 through the rod 29 and operable, upon energization of the magnet 34, to cause downward rotation of the members 28 about the bearing pin 3 supported in the downwardly extending flange portion 4 of the top wall of casing section 8. The electrode 27 being pivotally and guidingly connected with the lever members 28, the downward rotation of the latter effects the downward vertical movement of the electrode into circuit closing connection with the electrode 16. To effect upward vertical movement of the electrode 27 and thereby circuit opening operation of the device, upon the deenergization of magnet 34, I provide a compression spring arranged about the rod 29 and supported within the extension 26 between a disc 31, aflixed thereto, and the top wall of the casing section 8.

Briefly stated, the operation of the device, when arranged according to Fig. 1 as above described, is as follows: to effect circuit closing operation, the switch 37-indicated in the drawings as being manually operated, but which may, if desired, comprise a relay actuated automatically responsive to predetermined conditions occurring in the circuit to be controlled-is first closed to establish an energizing circuit, including a suitable source of current such as the battery 36, for the solenoid magnet 34 which then attracts the armature 33 downwardly into the solenoid. The downward movement of the armature 33 effects, through the interconnection of rod 29, the clockwise rotation of the lever members 28 and thereby the downward vertical movement of the electrode 27, carried thereby, through the aperture 9 into contact with the electrode 16, establishing thereby, electrical conductive connection of the conductor 17. with the conductor 38 serially through plate 13, electrodes 16 and 27, lever members 28, pivot 29, the walls of casing section 8. Current may then continue to flow over the circuit so long as the switch 37 remains in its circuit closing position. To thereafter efiect circuit opening operation of the device, the switch 37 is first actuated to its circuit opening position resulting thereby in the deenergization of the magnet 34, the return of armature 33 to the position shown and the rotation of the lever members 28, in a counterclockwise direction, carrying therewith the electrode 27 upwardly out of connection with the electrode 16.

At the moment of separation of the electrode 27 from the electrode 16 an arc will be struck at the surface of electrode 16 with resultant vaporization of a portion of the material thereof. Such are will then be maintained and current continue only for such period of time as might elapse until the current alternation passes through zero on its next alternation, as will be apparent to those skilled in the art, after which period of time the how of current will cease and the circuit interrupted. Upon such failure of the arc discharge between the electrodes 16, 27, the same will not be reestablished for the reason that the contact end of electrode 27 is then spaced vertically above electrode 16 an appreciable distance and will not be under such potenx tial as would be necessary to induce an are discharge, it being understood that at this time there would not be present a cathode spot" on the electrode 16 as the same will have then failed. It is to be particularly noted that during the movement of electrode 27 and the vapor of the arc upward through the throat of aperture 9 such vapor will be throttled and intensely cooled thus condensing a major portion thereof, thereby facilitating extinguishment of the arc and thus decreasing the time which would otherwise be necessary to interrupt the circuit. Closing of the circuit may again be effected by actuating switch 37 to its circuit closing position to excite the solenoid magnet 34, the latter being then effective to move the armature and the electrode 27 downward into contact with the electrode 16 as above described.

Fig. 2 illustrates an embodiment of the inven tion which differs structurally from the embodiment according to Fig. 1 substantially only in that, instead of forming the aperture 9 as a double cone having a constricted intermediate portion as in Fig. 1, such aperture is made cylindrical'and provided with pivotally mounted shutters 41 functioning as a double wing butterfly valve which are held open during circuit closing position of the device by the passage of the electrode 27 therethrough and which are caused to be closed during passage of the electrode 27 to circuit opening position of the device by the action of compression springs-42. The operation of the device differs, therefore, from the operation of the device according to Fig. 1 substantially only that in the arrangement according to Fig. 2 the extinguishment of the arc is facilitated by substantially barring the flow of vapor through the aperture 9 into contact with the electrode 27 by the closure of the shutters 41 immediately following movement of the contact end of the electrode 27 upward beyond the shutters 41. As in the embodiment according to Fig. 1, the arc once extinguished cannot be again established except by the connection and the following disconnection of electrode from electrode 16.

In the embodiment shown in Fig. 3, the top section 8 of the tank shown in Fig. l is omitted excepting for the dome 26 and the intermediate section 7 is modified in such manner that the arc struck upon separation of electrodes 16 and 27 is transferred to a fixed solid electrode 46 extending into a passageway 49, provided with cooling fins extending inwardly from the boundary wall through intermediate tank section 7 in insulated relation therewith. Means such as resistance 50 and grids 47, which may be connected as shown and described in U. S. Patent 1,856,155, issued May 3, 1932 to Maurice L. Sindeband and Othmar K. Marti, are provided to facilitate transfer of the ardfr m electrode 21 to electrode as as is well Y knofi in the electric power rectifier art. The arc must then pass through the relatively narrow opening 49 into the space about the electrode 48 whereby the vapor carrying the arc is rapidly con-' densed and the arc is quenched as soon as the current alternation passes through zero.

Fig. 4 illustrates a modiflcation embodying the principles illustrated in Figs. 2 and 3 in that shutters 41, operated by a weight 48 or other suitable means, are capable of closing a. passageway through section 'I and in which the top section takes the place. of the fixed electrode shown in Fig. 3. Transfers of the arc, struck upon lifting of electrode 27 out of electrode 16, to the top sec tion 8 is facilitated by the grid 4'1 controlled as is well-known in the electric power rectifier art.

when electrode 2'! is moved downwardly into electrode 16 as above described, electrode 27 contacts with weight 48 thereby raising the same and opening the shutters 41. The arc struck upon separation of electrodes 16 and 27 is transferred to the top 8 as explained with respect to Fig. 3 and is then interrupted upon passage of current through zero on its next alternation and/or by shutters 41 which are closed as soon as electrode 27 has moved far enough to permit weight 48 to drop. As in the embodiment according to Fig. 3, the are having been once transferred from the electrode 2'! to the wall of casing 8, cannot be again established with electrode 2'1 except as resulting from the contact thereof with the electrode 16 followed by the disconnection thereof from the electrode 16.-

It will be seen that the present invention provides means by which the phenomena known to occur in electric power rectiflers are utilized to interrupt electric circuits. The invention further provides a structure in which the arc struckiupon opening of the circuits is so much attenuated by condensation of the are carrying medium, which is the vapor from the electrode 16, as to cause positive quenching thereof when the current alternation passes through zero. The invention also provides for mechanical and electrical means toaid in quenching the arc. such means being available only with a structure such as disclosed in which the heat of-the arc is rapidly dissipated.

Although but a few embodiments of the present invention have been illustrated and described, it will be apparent to those skilled in the art that various changes and modifications may be made therein without departing from the spirit of the invention or from the scope of the appended claims.

The invention claimed is:

1. In a circuit breaker of the electric valve type, an evacuated casing having a portion thereof formed as an annular chamber for retaining a cooling medium and having an aperture therein forming a restricted passageway therethrough, a cathode electrode of vaporizable material and a movable anode electrode of solid material arranged within said casing and connected into an alternating current circuit to be controlled thereby, and means for moving said anode electrode through said passageway into and out of connection with said cathode electrode to thereby close said circuit and to create a vaporous arc for the flow of current of unidirection between said electrodes, the said chamber being operable to condense vapor created from said cathode electrode upon the establishment of said arc responsive to movement of said anode electrode from connection with said cathode electrode whereby the extinguishment of said are is facilitated and Y the opening of said circuit accelerated.

2. In a circuit breaker of the electric valve type. an evacuated casing having a portion thereof formed as an annular chamber for the circulation of a cooling medium therethrough and having an aperture therein forming a restricted passageway therethrough, a vaporizable reconstructing cathode electrode of mercury or other material electrically conductive in the vaporous state and a movable anode electrode of solid material arranged within said casing and connected into an alternating current circuit to be controlled thereby, and means for moving said anode electrode through said passageway into and out of connection with said cathode electrode to thereby close 'said circuit and to create a vaporous arc for the flow of current of unidirection between said electrodes, the said chamber being operable to deionize vapor created from said cathode electrode upon establishment of said arc responsive to movement of said anode electrode through said passageway from connection with said cathode electrode whereby the extinguishment of said arc is facilitated and the opening of said circuit thereby accelerated. I

3. In a circuit breaker of the electric valve type, an evacuated casing divided into a plurality of sections joined together in gas tight relation and providing a plurality of chambers having a constricted passageway extending therebetween, a vaporizable reconstructing cathode electrode of mercury or other material electrically conductive in the vaporous state retained within one of said chambers and a movable anode electrode of solid material supported within another of said chambers, the said electrodes being connected into an alternating current circuit to be controlled thereby, means for moving said anode electrode through said passageway into and out of connection with said cathode electrode to thereby close said circuit and to create a vaporous are for the flow of unidirectional current between said electrodes, and means for cooling said passageway to thereby condense and deionize vapor created from said cathode electrode and flowing into said passageway upon the establishment of said arc responsive to movement of said anode electrode from connection with said cathode electrode whereby the extinguishment of said arc is facilitated and the opening of said circuit thereby accelerated.

4. In a circuit breaker of the electric valve type. an evacuated casing having a portion thereof formed as an annular chamber for retaining a cooling medium and having an aperture therein forming a restricted passageway therethrough, a cathode electrode of vaporizable material and a movable anode electrode of solid material arranged within said casing and connected into an alternating current circuit to be controlled thereby, means for moving said anode electrode through said passageway into and out of connection with said cathode electrode to thereby close said circuit and to create a vaporous arc for the flow of current of unidirection through said passageway between said electrodes, the said chamber being operable to throttle the flowof vapor through said passageway upon the establishment of said are responsive to movement of said anode electrode through said passageway from connection with said cathode electrode whereby the extinguishment of said are is facilitated and the opening of said circuit thereby accelerated.

5. In a circuit breaker oi the electric valve m an evacuated casing having a portion there- 01 formed as an annular chamber for retaining a cooling medium and having an aperture therein forming a restricted passageway therethrough, a vaporizable reconstructing cathode electrode of mercury or other material electrically conductive in the vaporous state and a movable anode electrode or solid material, the said electrodes being arranged within said casing and connected into an alternating current circuit to be controlled thereby, means for moving said anode electrode through said passageway into and out of connection with said cathode electrode to close said circuit and to establish a vaporous are for the flow of current of unidirection between said electrodw, the said chamber being operable to cool said passageway to thereby condense and deionize vapor created from said cathode electrode upon establishment of said arc responsive to movement of said anode cathode through said passageway from connection with said cathode electrode, and means arranged within said passageway operable to throttle the flow 01' said vapor into said passageway, the last said means and the said condensing and deionizing of said vapor being operable to facilitate the extinguishment of said are whereby the opening of said circuit is accelerated.

6. In a circuit breaker oi the electric valve type, an evacuated chamber having a portion thereof formed as'a closed chamber for retaining a cooling medium and having an aperture therein forming a restricted passageway, a vaporizable reconstructing cathode electrode of mercury or other material electrically conductive in the vaporous state and an anode electrode of solid material arranged within said casing and connected into an alternating current circuit to be controlled thereby, and means for creating a vaporous are for the flow of current of unidirection through said passageway from said anode electrode to said cathode electrode, the said chamber being operable to condense and deionize the vapor of said are flowing through said passageway whereby extinguishment of said are is facilitated and the opening oi. said circuit thereby accelerated.

7. In a circuit breaker of the electric valve type, an evacuated tank divided into a plurality of sections joined together in gas tight relation and forming a plurality of interconnected chambers, a vaporizable reconstructing cathode electrode of mercury or other material electrically conductive in the vaporous state retained within one of said chambers, 'a. solid anode electrode supported within another of said chambers, the said electrodes being connected into an alternating current circuit to be controlled thereby, one of said sections being formed to provide a closed compartment for the circulation of a cooling fluid therethrough and having an aperture forming a restricted passageway between the said one and another chambers operable to efiect the condensation deionization of vapor tending to flow through said passageway, means for causing movement of said solid electrode through said passageway into and out of connection with said vaporizable electrode to effect closure of said circuit and the creation of a vaporous are for the flow of current of unidirection between said electrodes,and valve means arranged within said passageway automatically operable during movement of said solid electrode from connection with said vaporizable electrode to limit the flow oi vapor through said passageway, the said valve means and the circulation 01' said cooling fluid through said compartment being operable to facilitate the extinguishment of said arc created responsive to movement or said solid electrode from connection with said vaporizable electrode wtlgreby the opening of said circuit is acceler- 8,

8. In a circuit breaker oi the electric valve type, an evacuated tank divided into a plurality of sections joined together in gas tight relation and forming a plurality oi interconnected chambers, a vaporizable cathode electrode of mercury or other material electrically conductive in the vaporous state retained within one 0! said chambers, a solid anode electrode supported within another of said chambers, the said electrodes be ing connected into an alternating current circuit to be controlled, one 01' said sections of said tank being formed to provide a closed compartment for the flow of a cooling fluid therethrough and having an aperture therein forming a re-- stricted passageway between the said chambers, spring means operable to move said solid electrode through said aperture from connection with said vaporizable electrode to thereby establish a vaporous are for the flow of current of unidirection between saidelectrodes, and electromagnetic means operable to move said solid electrode through said aperture into connection with said vaporizable electrode to thereby ell'ect closure of said circuit, the said electromagnetic means being also operable to actuate said spring to render the latter operable. and the said aperture being so formed as to produce a throttling and condensing action on vapor tending to flow therethrough to thereby facilitate the extinguishment of said are created upon movement of said solid electrode through said passageway from connection with said vaporizable electrode whereby the opening of said circuit is accelerated.

9. In a circuit breaker of the electric valve type, an evacuated tank divided into a plurality of sections joined'together in a gas tight relation, one of said sections forming a chamber and 320 having a vaporizable reconstructing cathode electrode of mercury or other material electrically conductive in the vaporous state retained therein, another of said sections being formed to provide a closed compartment for the circulation of a cooling fluid therethrough and having a plurality of apertures opening into said chamber, a solid anode electrode supported for movement through one of said apertures, a fixed solid anode electrode supported within another of said apertures, the said electrodes being connected into an alternating current circuit to be controlled, means operable to effect movement of the first said solid electrode to and from connection with the said vaporizable electrode to thereby create a vaporous are for the flow of current of unidirection therebetween, and means operable to effect the transfer of said arc from the first said solid electrode to the second said solid electrode, the said another of said sections being operable to condense and restrict the flow of vapor through the said another of said apertures to the second said solid electrode to thereby facilitate the extinguishment of said arc whereby the opening of said circuit is accelerated.

10. In a circuit breaker of the electric valve type, an evacuated tank divided into a plurality of sections joined together in gas tight relation, one of said sections forming a chamber and having a vaporizable reconstructing cathode electrode of mercury or other material electrically conductive in the vaporous state retained therein, another of said sections being formed to provide a closed compartment for the circulation of a cooling fiuid therethrough and having a plurality of apertures opening into said chamber, a solid anode electrode supported for movement through one of said apertures, a fixed solid anode electrode supported within another of said apertures, the said electrodes being connected into an alternating current circuit to be controlled thereby, means operable to efiect movement of the first said solid electrode to and from connection with said vaporizable electrode to thereby create a vaporous are for the flow of current of unidirection therebetween, means for causing transfer of said are from the first said solid electrode to the second said solid electrode, and means associated with the second said solid electrode for facilitating the transfer of said arc thereto, the said another of said apertures being dimensioned to restrict the flow of the vapor of the arc therethrough to the second said. solid electrode and to condense such vapor to thereby facilitate the extinguishment of said are whereby the opening of said circuit is accelerated.

11. In a current circuit breaker of the electric valve type, an evacuated tank divided into a plurality of sections joined together in gas tight r e lation, one of said sections forming a chamber electrode of mercury or other material electrically conductive in the vaporous state retained therein, another of said sections being formed to provide a closed compartment for the flow of a cooling fluid therethrough and having a plurality of apertures opening into said chamber, a solid anode electrode supported for movement through one of said apertures, a fixed solid anode electrode supported within another of said apertures, the said electrodes being connected into an alternating current circuit to be controlled thereby, means operable to effect movement of the first said solid electrode through the said one of said apertures to and from connection with said vaporizable electrode to thereby create a vaporous are for the flow'of current of unidirection therebetween, means for causing transfer of said are from the first said solid electrode to the second said solid electrode, and an auxiliary electrode operable to facilitate the transfer of said arc from the first said solid electrode to the second said solid electrode, the said another of said apertures being dimensioned to restrict the flow of the vapor of said are therethrough to the second said solid electrode and to condense such vapor to thereby facilitate the extinguishment of said arc whereby the opening of said circuit is accelerated.

OTHMAR K. MARTI.

and having a vaporizable reconstructing cathode. 

